So what I have here is the Index wakeboard binding. The Index wakeboard binding features a size run from 5 to 8, 8 to 12, 12 to 15. The Index is an entry level boot, it actually features a duel gusset system. Here you can see flex, it actually allows the boot to accommodate those sizes. It features an easy glide system with pull tab and side lock to help lock it in. It’s on the SI plate system which is six inch spreads with three degree increment adjustment and also features a pillow top lining and lock in heel cup.